Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Although it was removed in commit 051e7cd4, ilock needs to be taken in
xfs_readdir because we might have to read the extent list in from disk.  This
keeps other threads from reading from or writing to the extent list while it is
being read in and is still in a transitional state.

This has been associated with "Access to block zero" messages on directories
with large numbers of extents resulting from excessive filesytem fragmentation,
as well as extent list corruption.  Unfortunately no test case at this point.
Signed-off-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

Equivalent to xfs_ilock_data_map_shared, except for the attribute fork.

Make xfs_getbmap use it if called for the attribute fork instead of
xfs_ilock_data_map_shared.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Make it clear that we're only locking against the extent map on the data
fork.  Also clean the function up a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

We can just use xfs_iunlock without any loss of clarity.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Both the inode number and the generation do not change on a live inode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

The function xfs_bmap_isaeof() is used to indicate that an
allocation is occurring at or past the end of file, and as such
should be aligned to the underlying storage geometry if possible.

Commit 27a3f8f2 ("xfs: introduce xfs_bmap_last_extent") changed the
behaviour of this function for empty files - it turned off
allocation alignment for this case accidentally. Hence large initial
allocations from direct IO are not getting correctly aligned to the
underlying geometry, and that is cause write performance to drop in
alignment sensitive configurations.

Fix it by considering allocation into empty files as requiring
aligned allocation again.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

rec.ir_startino is an agino rather than an ino.  Use the correct macro
when dealing with it in xfs_difree.
Signed-off-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

When I tried to send the patches to XFS Maintainers,
I got returned mail included delivery fail message for Dave's mail.
Maybe, Dave Chinner mail address is incorrect.
I try to fix it correctly.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

If we are using a large directory block size, and memory becomes
fragmented, we can get memory allocation failures trying to
kmem_alloc(64k) for a temporary buffer. However, there is not need
for a directory buffer sized allocation, as the end result ends up
in the inode literal area. This is, at most, slightly less than 2k
of space, and hence we don't need an allocation larger than that
fora temporary buffer.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

xfs_quota(8) will hang up if trying to turn group/project quota off
before the user quota is off, this could be 100% reproduced by:
  # mount -ouquota,gquota /dev/sda7 /xfs
  # mkdir /xfs/test
  # xfs_quota -xc 'off -g' /xfs <-- hangs up
  # echo w > /proc/sysrq-trigger
  # dmesg

  SysRq : Show Blocked State
  task                        PC stack   pid father
  xfs_quota       D 0000000000000000     0 27574   2551 0x00000000
  [snip]
  Call Trace:
  [<ffffffff81aaa21d>] schedule+0xad/0xc0
  [<ffffffff81aa327e>] schedule_timeout+0x35e/0x3c0
  [<ffffffff8114b506>] ? mark_held_locks+0x176/0x1c0
  [<ffffffff810ad6c0>] ? call_timer_fn+0x2c0/0x2c0
  [<ffffffffa0c25380>] ? xfs_qm_shrink_count+0x30/0x30 [xfs]
  [<ffffffff81aa3306>] schedule_timeout_uninterruptible+0x26/0x30
  [<ffffffffa0c26155>] xfs_qm_dquot_walk+0x235/0x260 [xfs]
  [<ffffffffa0c059d8>] ? xfs_perag_get+0x1d8/0x2d0 [xfs]
  [<ffffffffa0c05805>] ? xfs_perag_get+0x5/0x2d0 [xfs]
  [<ffffffffa0b7707e>] ? xfs_inode_ag_iterator+0xae/0xf0 [xfs]
  [<ffffffffa0c22280>] ? xfs_trans_free_dqinfo+0x50/0x50 [xfs]
  [<ffffffffa0b7709f>] ? xfs_inode_ag_iterator+0xcf/0xf0 [xfs]
  [<ffffffffa0c261e6>] xfs_qm_dqpurge_all+0x66/0xb0 [xfs]
  [<ffffffffa0c2497a>] xfs_qm_scall_quotaoff+0x20a/0x5f0 [xfs]
  [<ffffffffa0c2b8f6>] xfs_fs_set_xstate+0x136/0x180 [xfs]
  [<ffffffff8136cf7a>] do_quotactl+0x53a/0x6b0
  [<ffffffff812fba4b>] ? iput+0x5b/0x90
  [<ffffffff8136d257>] SyS_quotactl+0x167/0x1d0
  [<ffffffff814cf2ee>] ? trace_hardirqs_on_thunk+0x3a/0x3f
  [<ffffffff81abcd19>] system_call_fastpath+0x16/0x1b

It's fine if we turn user quota off at first, then turn off other
kind of quotas if they are enabled since the group/project dquot
refcount is decreased to zero once the user quota if off. Otherwise,
those dquots refcount is non-zero due to the user dquot might refer
to them as hint(s).  Hence, above operation cause an infinite loop
at xfs_qm_dquot_walk() while trying to purge dquot cache.

This problem has been around since Linux 3.4, it was introduced by:
  [ b84a3a96 xfs: remove the per-filesystem list of dquots ]

Originally we will release the group dquot pointers because the user
dquots maybe carrying around as a hint via xfs_qm_detach_gdquots().
However, with above change, there is no such work to be done before
purging group/project dquot cache.

In order to solve this problem, this patch introduces a special routine
xfs_qm_dqpurge_hints(), and it would release the group/project dquot
pointers the user dquots maybe carrying around as a hint, and then it
will proceed to purge the user dquot cache if requested.

Cc: stable@vger.kernel.org
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

For CRC enabled v5 super block, change a file's ownership can simply
trigger an ASSERT failure at xfs_setattr_nonsize() if both group and
project quota are enabled, i.e,

[  305.337609] XFS: Assertion failed: !XFS_IS_PQUOTA_ON(mp), file: fs/xfs/xfs_iops.c, line: 621
[  305.339250] Kernel BUG at ffffffffa0a7fa32 [verbose debug info unavailable]
[  305.383939] Call Trace:
[  305.385536]  [<ffffffffa0a7d95a>] xfs_setattr_nonsize+0x69a/0x720 [xfs]
[  305.387142]  [<ffffffffa0a7dea9>] xfs_vn_setattr+0x29/0x70 [xfs]
[  305.388727]  [<ffffffff811ca388>] notify_change+0x1a8/0x350
[  305.390298]  [<ffffffff811ac39d>] chown_common+0xfd/0x110
[  305.391868]  [<ffffffff811ad6bf>] SyS_fchownat+0xaf/0x110
[  305.393440]  [<ffffffff811ad760>] SyS_lchown+0x20/0x30
[  305.394995]  [<ffffffff8170f7dd>] system_call_fastpath+0x1a/0x1f
[  305.399870] RIP  [<ffffffffa0a7fa32>] assfail+0x22/0x30 [xfs]

This fix adjust the assertion to check if the super block support both
quota inodes or not.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

Split out a xfs_setattr_time helper to share code between truncate and
regular setattr similar to xfs_setattr_mode.  I might also have another
caller growing for this in the near future.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Remove the pointless tp argument, and properly align the local variable
declarations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

After the previous fix, there still has another ASSERT failure if turning
off any type of quota while fsstress is running at the same time.

Backtrace in this case:

[   50.867897] XFS: Assertion failed: XFS_IS_GQUOTA_ON(mp), file: fs/xfs/xfs_qm.c, line: 2118
[   50.867924] ------------[ cut here ]------------
... <snip>
[   50.867957] Kernel BUG at ffffffffa0b55a32 [verbose debug info unavailable]
[   50.867999] invalid opcode: 0000 [#1] SMP
[   50.869407] Call Trace:
[   50.869446]  [<ffffffffa0bc408a>] xfs_qm_vop_create_dqattach+0x19a/0x2d0 [xfs]
[   50.869512]  [<ffffffffa0b9cc45>] xfs_create+0x5c5/0x6a0 [xfs]
[   50.869564]  [<ffffffffa0b5307c>] xfs_vn_mknod+0xac/0x1d0 [xfs]
[   50.869615]  [<ffffffffa0b531d6>] xfs_vn_mkdir+0x16/0x20 [xfs]
[   50.869655]  [<ffffffff811becd5>] vfs_mkdir+0x95/0x130
[   50.869689]  [<ffffffff811bf63a>] SyS_mkdirat+0xaa/0xe0
[   50.869723]  [<ffffffff811bf689>] SyS_mkdir+0x19/0x20
[   50.869757]  [<ffffffff8170f7dd>] system_call_fastpath+0x1a/0x1f
[   50.869793] Code: 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 <snip>
[   50.870003] RIP  [<ffffffffa0b55a32>] assfail+0x22/0x30 [xfs]
[   50.870050]  RSP <ffff88002941fd60>
[   50.879251] ---[ end trace c93a2b342341c65b ]---

We're hitting the ASSERT(XFS_IS_*QUOTA_ON(mp)) in xfs_qm_vop_create_dqattach(),
however the assertion itself is not right IMHO.  While performing quota off, we
firstly clear the XFS_*QUOTA_ACTIVE bit(s) from struct xfs_mount without taking
any special locks, see xfs_qm_scall_quotaoff().  Hence there is no guarantee
that the desired quota is still active.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

The xfs_quota_priv header file is only included by xfs_qm header and
there is no much users for its contents, hence we can move those stuff
to xfs_qm header file and kill it.

This patch also remove an unused macro DQFLAGTO_TYPESTR.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

In xfs_qm_scall_trunc_qfiles(), we ignore the error if failed to remove
the users quota metadata and proceed to remove groups and projects if
they are being there.  However, in user space, the remove operation will
break and return if failed to remove any kind of quota.
Also for v5 super block, we can enabled both group and project quota at
the same time, in this case the current error handling will cover the
group error with projects but they might failed due to different reasons.

It seems we'd better the error handling consistent to the user space and
don't trying to remove another kind of quota metadata if the previous
operation is failed.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

Fix the leak of kernel memory in xfs_dir2_node_removename()
when xfs_dir2_leafn_remove() returns an error code.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Recovery builds a list of items on the transaction's
r_itemq head. Normally these items are committed and freed.
But in the event of a recovery error, these allocations
are leaked.

If the error occurs during item reordering, then reconstruct
the r_itemq list before deleting the list to avoid leaking
the entries that were on one of the temporary lists.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Currently notify_change directly updates i_version for size updates,
which not only is counter to how all other fields are updated through
struct iattr, but also breaks XFS, which need inode updates to happen
under its own lock, and synchronized to the structure that gets written
to the log.

Remove the update in the common code, and it to btrfs and ext4,
XFS already does a proper updaste internally and currently gets a
double update with the existing code.

IMHO this is 3.13 and -stable material and should go in through the XFS
tree.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Acked-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

This loop in xfs_growfs_data_private() is incorrect for V4
superblocks filesystems:

		for (bucket = 0; bucket < XFS_AGFL_SIZE(mp); bucket++)
			agfl->agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);

For V4 filesystems, we don't have a agfl header structure, and so
XFS_AGFL_SIZE() returns an entire sector's worth of entries, which
we then index from an offset into the sector. Hence: buffer overrun.

This problem was introduced in 3.10 by commit 77c95bba ("xfs: add
CRC checks to the AGFL") which changed the AGFL structure but failed
to update the growfs code to handle the different structures.

Fix it by using the correct offset into the buffer for both V4 and
V5 filesystems.

Cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

For discard operation, we should return EINVAL if the given range length
is less than a block size, otherwise it will go through the file system
to discard data blocks as the end range might be evaluated to -1, e.g,
# fstrim -v -o 0 -l 100 /xfs7
/xfs7: 9811378176 bytes were trimmed

This issue can be triggered via xfstests/generic/288.

Also, it seems to get the request queue pointer via bdev_get_queue()
instead of the hard code pointer dereference is not a bad thing.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

If we allocate less than sizeof(struct attrlist) then we end up
corrupting memory or doing a ZERO_PTR_SIZE dereference.

This can only be triggered with CAP_SYS_ADMIN.
Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@redhat.com.>
Signed-off-by: Ben Myers <bpm@sgi.com>

The "verbose" argument to xfs_setsize_buftarg_flags() has been
unused since:

ffe37436 xfs: stop using the page cache to back the buffer cache

Remove it, and fold the function into xfs_setsize_buftarg()
now that there's no need for different types of callers.

Fix inconsistent comment spacing while we're at it.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Pull ARM64 fixes from Catalin Marinas:
 - Remove preempt_count modifications in the arm64 IRQ handling code
   since that's already dealt with in generic irq_enter/irq_exit
 - PTE_PROT_NONE bit moved higher up to avoid overlapping with the
   hardware bits (for PROT_NONE mappings which are pte_present)
 - Big-endian fixes for ptrace support
 - Asynchronous aborts unmasking while in the kernel
 - pgprot_writecombine() change to create Normal NonCacheable memory
   rather than Device GRE

* tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: Move PTE_PROT_NONE higher up
  arm64: Use Normal NonCacheable memory for writecombine
  arm64: debug: make aarch32 bkpt checking endian clean
  arm64: ptrace: fix compat registes get/set to be endian clean
  arm64: Unmask asynchronous aborts when in kernel mode
  arm64: dts: Reserve the memory used for secondary CPU release address
  arm64: let the core code deal with preempt_count

Pull s390 updates from Martin Schwidefsky:
 "One performance improvement and a few bug fixes.  Two of the fixes
  deal with the clock related problems we have seen on recent kernels"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/mm: handle asce-type exceptions as normal page fault
  s390,time: revert direct ktime path for s390 clockevent device
  s390/time,vdso: convert to the new update_vsyscall interface
  s390/uaccess: add missing page table walk range check
  s390/mm: optimize copy_page
  s390/dasd: validate request size before building CCW/TCW request
  s390/signal: always restore saved runtime instrumentation psw bit

Pull i2c fixes from Wolfram Sang:
 "Some easy but needed fixes for i2c drivers since rc1"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: bcm2835: Linking platform nodes to adapter nodes
  i2c: omap: raw read and write endian fix
  i2c: i2c-bcm-kona: Fix module build
  i2c: i2c-diolan-u2c: different usb endpoints for DLN-2-U2C
  i2c: bcm-kona: remove duplicated include
  i2c: davinci: raw read and write endian fix

Pull workqueue fixes from Tejun Heo:
 "This contains one important fix.  The NUMA support added a while back
  broke ordering guarantees on ordered workqueues.  It was enforced by
  having single frontend interface with @max_active == 1 but the NUMA
  support puts multiple interfaces on unbound workqueues on NUMA
  machines thus breaking the ordered guarantee.  This is fixed by
  disabling NUMA support on ordered workqueues.

  The above and a couple other patches were sitting in for-3.12-fixes
  but I forgot to push that out, so they ended up waiting a bit too
  long.  My aplogies.

  Other fixes are minor"

* 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix pool ID allocation leakage and remove BUILD_BUG_ON() in init_workqueues
  workqueue: fix comment typo for __queue_work()
  workqueue: fix ordered workqueues in NUMA setups
  workqueue: swap set_cpus_allowed_ptr() and PF_NO_SETAFFINITY

Pull libata fixes from Tejun Heo:
 "libata device removal path was removing parent device node before its
  child, which is mostly harmless but triggers warning after recent
  sysfs changes.  Rafael's patch fixes the order.

  Other than that, minor controller-specific fixes and device ID
  additions"

* 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ATA: Fix port removal ordering
  ahci: add Marvell 9230 to the AHCI PCI device list
  ata: fix acpi_bus_get_device() return value check
  pata_arasan_cf: add missing clk_disable_unprepare() on error path
  ahci: add support for IBM Akebono platform device

Pull cgroup fixes from Tejun Heo:
 "Fixes for three issues.

   - cgroup destruction path could swamp system_wq possibly leading to
     deadlock.  This actually seems to happen in the wild with memcg
     because memcg destruction path adds nested dependency on system_wq.

     Resolved by isolating cgroup destruction work items on its
     dedicated workqueue.

   - Possible locking context deadlock through seqcount reported by
     lockdep

   - Memory leak under certain conditions"

* 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix cgroup_subsys_state leak for seq_files
  cpuset: Fix memory allocator deadlock
  cgroup: use a dedicated workqueue for cgroup destruction

Pull sound fixes from Takashi Iwai:
 "Quite a few HD-Audio fixes, a WUSB audio fix and a fix for FireWire
  audio.  The HD-audio part contains a couple of fixes for the generic
  parser, and these are the only intrusive fixes.  The rest are mostly
  device-specific fixes"

* tag 'sound-3.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Add LFE chmap to ASUS ET2700
  ALSA: hda - Initialize missing bass speaker pin for ASUS AIO ET2700
  ALSA: hda - limit mic boost on Asus UX31[A,E]
  ALSA: hda - Check leaf nodes to find aamix amps
  ALSA: hda - Fix hp-mic mode without VREF bits
  ALSA: hda - Create Headhpone Mic Jack Mode when really needed
  ALSA: usb: use multiple packets per urb for Wireless USB inbound audio
  ALSA: hda - Enable mute/mic-mute LEDs for more Thinkpads with Conexant codec
  ALSA: hda - Drop bus->avoid_link_reset flag
  ALSA: hda/realtek - Set pcbeep amp for ALC668
  ALSA: hda/realtek - Add support of ALC231 codec
  ALSA: firewire-lib: fix wrong value for FDF field as an empty packet

Pull vfs dentry reference count fix from Al Viro.

This fixes a possible inode_permission NULL pointer dereference (and
other problems) that were due to the root dentry count being decremented
too much.  In commit 48a066e7 ("RCU'd vfsmounts") the placement of
clearing the LOOKUP_RCU bit changed, and we then returned failure of
incrementing the lockref on the parent dentry with LOOKUP_RCU cleared.

But that meant we needed to go through the same cleanup routines that
the later failures did wrt LOOKUP_ROOT and nd->root.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix bogus path_put() of nd->root after some unlazy_walk() failures

Pull drm qxl leak fix from Dave Airlie:
 "As usual 5 mins after I send a trivial pull fix I find a real bug!

  This fixes a memory leak and I'd like to get it into stable queue
  asap"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/qxl: fix memory leak in release list handling

PTE_PROT_NONE means that a pte is present but does not have any
read/write attributes. However, setting the memory type like
pgprot_writecombine() is allowed and such bits overlap with
PTE_PROT_NONE. This causes mmap/munmap issues in drivers that change the
vma->vm_pg_prot on PROT_NONE mappings.

This patch reverts the PTE_FILE/PTE_PROT_NONE shift in commit
59911ca4 (ARM64: mm: Move PTE_PROT_NONE bit) and moves PTE_PROT_NONE
together with the other software bits.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Steve Capper <steve.capper@linaro.org>
Cc: <stable@vger.kernel.org> # 3.11+

This provides better performance compared to Device GRE and also allows
unaligned accesses. Such memory is intended to be used with standard RAM
(e.g. framebuffers) and not I/O.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Failure to grab reference to parent dentry should go through the
same cleanup as nd->seq mismatch.  As it is, we might end up with
caller thinking it needs to path_put() nd->root, with obvious
nasty results once we'd hit that bug enough times to drive the
refcount of root dentry all the way to zero...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

wow no idea how I got this far without seeing this,
leaking the entries in the list makes kmalloc-64 slab grow.

References: https://bugzilla.kernel.org/show_bug.cgi?id=65121
Cc: stable@vger.kernel.org
Reported-by: Matthew Stapleton <matthew4196@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>